#include <iostream>
#include <fstream>
#include <string>
#include <vector>
#include <regex>
#include <sys/stat.h>
#include "../server.hpp"
#include<assert.h>
#define DEFALT_TIMEOUT 10
std::unordered_map<int, std::string> _statu_msg = {
    {100,  "Continue"},
    {101,  "Switching Protocol"},
    {102,  "Processing"},
    {103,  "Early Hints"},
    {200,  "OK"},
    {201,  "Created"},
    {202,  "Accepted"},
    {203,  "Non-Authoritative Information"},
    {204,  "No Content"},
    {205,  "Reset Content"},
    {206,  "Partial Content"},
    {207,  "Multi-Status"},
    {208,  "Already Reported"},
    {226,  "IM Used"},
    {300,  "Multiple Choice"},
    {301,  "Moved Permanently"},
    {302,  "Found"},
    {303,  "See Other"},
    {304,  "Not Modified"},
    {305,  "Use Proxy"},
    {306,  "unused"},
    {307,  "Temporary Redirect"},
    {308,  "Permanent Redirect"},
    {400,  "Bad Request"},
    {401,  "Unauthorized"},
    {402,  "Payment Required"},
    {403,  "Forbidden"},
    {404,  "Not Found"},
    {405,  "Method Not Allowed"},
    {406,  "Not Acceptable"},
    {407,  "Proxy Authentication Required"},
    {408,  "Request Timeout"},
    {409,  "Conflict"},
    {410,  "Gone"},
    {411,  "Length Required"},
    {412,  "Precondition Failed"},
    {413,  "Payload Too Large"},
    {414,  "URI Too Long"},
    {415,  "Unsupported Media Type"},
    {416,  "Range Not Satisfiable"},
    {417,  "Expectation Failed"},
    {418,  "I'm a teapot"},
    {421,  "Misdirected Request"},
    {422,  "Unprocessable Entity"},
    {423,  "Locked"},
    {424,  "Failed Dependency"},
    {425,  "Too Early"},
    {426,  "Upgrade Required"},
    {428,  "Precondition Required"},
    {429,  "Too Many Requests"},
    {431,  "Request Header Fields Too Large"},
    {451,  "Unavailable For Legal Reasons"},
    {501,  "Not Implemented"},
    {502,  "Bad Gateway"},
    {503,  "Service Unavailable"},
    {504,  "Gateway Timeout"},
    {505,  "HTTP Version Not Supported"},
    {506,  "Variant Also Negotiates"},
    {507,  "Insufficient Storage"},
    {508,  "Loop Detected"},
    {510,  "Not Extended"},
    {511,  "Network Authentication Required"}
};

std::unordered_map<std::string, std::string> _mime_msg = {
    {".aac",        "audio/aac"},
    {".abw",        "application/x-abiword"},
    {".arc",        "application/x-freearc"},
    {".avi",        "video/x-msvideo"},
    {".azw",        "application/vnd.amazon.ebook"},
    {".bin",        "application/octet-stream"},
    {".bmp",        "image/bmp"},
    {".bz",         "application/x-bzip"},
    {".bz2",        "application/x-bzip2"},
    {".csh",        "application/x-csh"},
    {".css",        "text/css"},
    {".csv",        "text/csv"},
    {".doc",        "application/msword"},
    {".docx",       "application/vnd.openxmlformats-officedocument.wordprocessingml.document"},
    {".eot",        "application/vnd.ms-fontobject"},
    {".epub",       "application/epub+zip"},
    {".gif",        "image/gif"},
    {".htm",        "text/html"},
    {".html",       "text/html"},
    {".ico",        "image/vnd.microsoft.icon"},
    {".ics",        "text/calendar"},
    {".jar",        "application/java-archive"},
    {".jpeg",       "image/jpeg"},
    {".jpg",        "image/jpeg"},
    {".js",         "text/javascript"},
    {".json",       "application/json"},
    {".jsonld",     "application/ld+json"},
    {".mid",        "audio/midi"},
    {".midi",       "audio/x-midi"},
    {".mjs",        "text/javascript"},
    {".mp3",        "audio/mpeg"},
    {".mpeg",       "video/mpeg"},
    {".mpkg",       "application/vnd.apple.installer+xml"},
    {".odp",        "application/vnd.oasis.opendocument.presentation"},
    {".ods",        "application/vnd.oasis.opendocument.spreadsheet"},
    {".odt",        "application/vnd.oasis.opendocument.text"},
    {".oga",        "audio/ogg"},
    {".ogv",        "video/ogg"},
    {".ogx",        "application/ogg"},
    {".otf",        "font/otf"},
    {".png",        "image/png"},
    {".pdf",        "application/pdf"},
    {".ppt",        "application/vnd.ms-powerpoint"},
    {".pptx",       "application/vnd.openxmlformats-officedocument.presentationml.presentation"},
    {".rar",        "application/x-rar-compressed"},
    {".rtf",        "application/rtf"},
    {".sh",         "application/x-sh"},
    {".svg",        "image/svg+xml"},
    {".swf",        "application/x-shockwave-flash"},
    {".tar",        "application/x-tar"},
    {".tif",        "image/tiff"},
    {".tiff",       "image/tiff"},
    {".ttf",        "font/ttf"},
    {".txt",        "text/plain"},
    {".vsd",        "application/vnd.visio"},
    {".wav",        "audio/wav"},
    {".weba",       "audio/webm"},
    {".webm",       "video/webm"},
    {".webp",       "image/webp"},
    {".woff",       "font/woff"},
    {".woff2",      "font/woff2"},
    {".xhtml",      "application/xhtml+xml"},
    {".xls",        "application/vnd.ms-excel"},
    {".xlsx",       "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"},
    {".xml",        "application/xml"},
    {".xul",        "application/vnd.mozilla.xul+xml"},
    {".zip",        "application/zip"},
    {".3gp",        "video/3gpp"},
    {".3g2",        "video/3gpp2"},
    {".7z",         "application/x-7z-compressed"}
};
//工具类
class Util{
public:
    //字符串分割,将src字符串按照sep字符进行分割，得到的各个字串放到arry中，最终返回字串的数量
    static size_t Split(const std::string& src,const std::string& sep,std::vector<std::string>*arry){
        size_t offset = 0;
        // 有10个字符，offset是查找的起始位置，范围应该是0~9，offset==10就代表已经越界了
        //1.确保分割范围有效
        while(offset==src.size()){
            size_t pos = src.find(sep,offset);//在src字符串偏移量offset处，开始向后查找sep字符/字串，返回查找到的位置
            //2.没有找到特定分割符
            if(pos==std::string::npos){
                //将剩余的部分当作一个字串，放入arry中
                if(pos==src.size())break;
                arry->push_back(src.substr(offset));
                return arry->size();
            }
            //3.当前字串是一个空的，没有内容
            if(pos==offset){
                offset = pos+sep.size();
                continue;
            }
            //4.把分割出的字符放入数组中
            arry->push_back(src.substr(offset,pos-offset));
            offset = pos+sep.size();
        }
        //5.返回个数
        return arry->size();
    }
    //读取文件的所有内容，将读取的内容放到一个Buffer中
    static bool ReadFile(const std::string& filename,std::string* buf){
        //1.二进制模式打开文件
        std::ifstream ifs(filename,std::ios::binary);
        if(ifs.is_open()==false){
            printf("OPEN %s FILE FAILED!!", filename.c_str());
            return false;
        }
        //2.获取读取内容大小
        size_t fsize = 0;
        ifs.seekg(0,ifs.end);// 将读取指针移动到文件末尾
        fsize = ifs.tellg();// 获取当前位置（即文件末尾）的偏移量，这就是文件大小
        ifs.seekg(0,ifs.beg);//将读取指针重新移动到文件开头，准备读取
        //3.开辟存储空间大小读取
        buf->resize(fsize);
        ifs.read(&(*buf)[0],fsize);
        //4.判断读取是否成功
        if(ifs.good()==false){
            printf("READ %s FILE FAILED!!", filename.c_str());
            ifs.close();
            return false;
        }
        //5.关闭文件并返回成功
        ifs.close();
        return true;
    }
    //向文件写入数据
    static bool WriteFile(const std::string &filename, const std::string &buf){
        // 1. 以二进制模式打开文件，并清空文件内容
        std::ofstream ofs(filename, std::ios::binary | std::ios::trunc);
        if (ofs.is_open() == false) {
            printf("OPEN %s FILE FAILED!!", filename.c_str());
            return false;
        }
        // 2. 将字符串数据写入文件
        ofs.write(buf.c_str(), buf.size());
        // 3. 检查写入是否成功
        if (ofs.good() == false) {
            ERR_LOG("WRITE %s FILE FAILED!", filename.c_str());
            ofs.close();    
            return false;
        }
        // 4. 关闭文件并返回成功
        ofs.close();
        return true;
    }
    //URL编码，避免URL中资源路径与查询字符串中的特殊字符与HTTP请求中特殊字符产生歧义
    //编码格式：将特殊字符的ascii值，转换为两个16进制字符，前缀%   C++ -> C%2B%2B
    //  不编码的特殊字符： RFC3986文档规定 . - _ ~ 字母，数字属于绝对不编码字符
    //RFC3986文档规定，编码格式 %HH 
    //W3C标准中规定，查询字符串中的空格是需要编码为+， 解码则是+转空格
    //特殊字符转16进制
    static std::string UrlEncode(const std::string url, bool convert_space_to_plus){
        std::string res;
        for(auto& c:url){
            //1.排查不可转换字符和特殊字符
            if(c == '.' || c == '-' || c == '_' || c == '~' || isalnum(c)){
                res += c;
                continue;
            }
            if(c == ' ' && convert_space_to_plus == true){
                res += '+';
                continue;
            }
            //2.剩下的字符都是需要编码成为 %HH 格式
            char tmp[4]={0};
            //snprintf格式化字符串,将字符串c格式成特定格式放入tmp中
            snprintf(tmp,4,"%%%02X",c);
            res += tmp;
        }
        return res;
    }
    static char HEXTOI(char c){
        // 十六进制字符转换为数字
        if (c >= '0' && c <= '9') {
            return c - '0';          // '0'-'9' -> 0-9
        }else if (c >= 'a' && c <= 'z') {
            return c - 'a' + 10;     // 'a'-'z' -> 10-35
        }else if (c >= 'A' && c <= 'Z') {
            return c - 'A' + 10;     // 'A'-'Z' -> 10-35
        }
        return -1; // 非法字符返回-1
    }
    //URL解码
    static std::string UrlDecode(const std::string url, bool convert_plus_to_space){
        //遇到了%，则将紧随其后的2个字符，转换为数字，第一个数字左移4位，然后加上第二个数字  + -> 2b  %2b->2 << 4 + 11
        std::string res;
        for (int i = 0; i < url.size(); i++) {
            // 1. 处理 '+' 转换为空格
            if (url[i] == '+' && convert_plus_to_space == true) {
                res += ' ';
                continue;
            }
            // 2. 处理百分号编码 '%XX'
            if (url[i] == '%' && (i + 2) < url.size()) {
                char v1 = HEXTOI(url[i + 1]);  // 第一个十六进制字符转数字
                char v2 = HEXTOI(url[i + 2]);  // 第二个十六进制字符转数字
                // 组合成原始字符: v1 * 16 + v2
                // 例如: %2B -> v1=2, v2=11 -> 2*16 + 11 = 43 ('+')
                char v = v1 * 16 + v2;
                res += v;
                i += 2;  // 跳过已处理的2个十六进制字符
                continue;
            }
            // 3. 普通字符直接添加
            res += url[i];
        }
        return res;
    }
    //响应状态码的描述信息获取
    static std::string StatuDesc(int statu){
        auto it = _statu_msg.find(statu);
        if (it != _statu_msg.end()) {
            return it->second;
        }
        return "Unknow";
    }
    //根据文件后缀名获取文件mime
    static std::string ExtMime(const std::string &filename){
        //1. a.b.txt  先获取文件扩展名
        size_t pos = filename.find_last_of('.');
        if (pos == std::string::npos) {
            return "application/octet-stream";
        }
        //2.根据扩展名，获取mime
        std::string ext = filename.substr(pos);
        auto it = _mime_msg.find(ext);
        if (it == _mime_msg.end()) {
            return "application/octet-stream";
        }
        return it->second;
    }
    //判断一个文件是否是一个目录
    static bool IsDirectory(const std::string &filename){
        struct stat st;
        int ret = stat(filename.c_str(), &st);
        if (ret < 0) {
            return false;
        }
        return S_ISDIR(st.st_mode);
    }
    //判断一个文件是否是一个普通文件
    static bool IsRegular(const std::string &filename){
        struct stat st;
        int ret = stat(filename.c_str(), &st);
        if (ret < 0) {
            return false;
        }
        return S_ISREG(st.st_mode);
    }
    //http请求的资源路径有效性判断
    // /index.html  --- 前边的/叫做相对根目录  映射的是某个服务器上的子目录
    // 想表达的意思就是，客户端只能请求相对根目录中的资源，其他地方的资源都不予理会
    // /../login, 这个路径中的..会让路径的查找跑到相对根目录之外，这是不合理的，不安全的
    static bool ValidPath(const std::string &path){
        //1.按照/进行路径分割
        std::vector<std::string> subdir;
        Split(path, "/", &subdir);// 假设Split函数存在，按分隔符分割字符串
        int level = 0; // 当前目录深度计数器

        // 2. 遍历每个子目录
        for (auto &dir : subdir) {
            if (dir == "..") {
                level--; // 遇到".."，目录深度减1（向上一级）
                if (level < 0) return false;// 如果深度小于0，说明跳出了根目录
                continue;
            }
            level++;// 普通目录，深度加1
        }
        return true;// 路径合法
    }  
};
class HttpRequest{
public:
    std::string _method;//请求方法
    std::string _path;//资源路径
    std::string _version;//协议版本
    std::string _body;//请求正文
    std::smatch _matches;//资源路径的正则提取数据
    std::unordered_map<std::string,std::string> _headers;//头部字段
    std::unordered_map<std::string,std::string> _params;//查询字符串
public:
    HttpRequest():_version("HTTP/1.1"){}
    void ReSet(){
        _method.clear();
        _path.clear();
        _version="HTTP/1.1";
        _body.clear();
        std::smatch match;
        _matches.swap(match);
        _headers.clear();
        _params.clear();
    }
    //插入头部字段
    void SetHeader(const std::string &key, const std::string &val) {
        _headers.insert(std::make_pair(key, val));
    }
    //通过key判断是否存在指定头部字段
    bool HasHeader(const std::string &key) const {
        auto it = _headers.find(key);
        if (it == _headers.end()) {
            return false;
        }
        return true;
    }
    //获取指定头部字段的值，还是通过key查找返回
    std::string GetHeader(const std::string &key) const {
        auto it = _headers.find(key);
        if (it == _headers.end()) {
            return "";
        }
        return it->second;
    }
    //插入查询字符串
    void SetParam(const std::string &key, const std::string &val) {
        _params.insert(std::make_pair(key, val));
    }
    //判断是否有某个指定的查询字符串
    bool HasParam(const std::string &key) const {
        auto it = _params.find(key);
        if (it == _params.end()) {
            return false;
        }
        return true;
    }
    //获取指定的查询字符串
    std::string GetParam(const std::string &key) const {
        auto it = _params.find(key);
        if (it == _params.end()) {
            return "";
        }
        return it->second;
    }
    //获取正文长度
    size_t ContentLength() const {
        // Content-Length: 1234\r\n
        bool ret = HasHeader("Content-Length");
        if (ret == false) {
            return 0;
        }
        std::string clen = GetHeader("Content-Length");
        return std::stol(clen);
    }
    //判断是否是短链接
    bool Close() const {
        // 没有Connection字段，或者有Connection但是值是close，则都是短链接，否则就是长连接
        if (HasHeader("Connection") == true && GetHeader("Connection") == "keep-alive") {
            return false;
        }
        return true;
    }
};
class HttpResponse {
public:
    int _statu;
    bool _redirect_flag;
    std::string _body;
    std::string _redirect_url;
    std::unordered_map<std::string, std::string> _headers;
public:
    HttpResponse():_redirect_flag(false), _statu(200) {}
    HttpResponse(int statu):_redirect_flag(false), _statu(statu) {} 
    void ReSet() {
        _statu = 200;
        _redirect_flag = false;
        _body.clear();
        _redirect_url.clear();
        _headers.clear();
    }
    //插入头部字段
    void SetHeader(const std::string &key, const std::string &val) {
        _headers.insert(std::make_pair(key, val));
    }
    //判断是否存在指定头部字段
    bool HasHeader(const std::string &key) {
        auto it = _headers.find(key);
        if (it == _headers.end()) {
            return false;
        }
        return true;
    }
    //获取指定头部字段的值
    std::string GetHeader(const std::string &key) {
        auto it = _headers.find(key);
        if (it == _headers.end()) {
            return "";
        }
        return it->second;
    }
    void SetContent(const std::string &body,  const std::string &type = "text/html") {
        _body = body;
        SetHeader("Content-Type", type);
    }
    void SetRedirect(const std::string &url, int statu = 302) {
        _statu = statu;
        _redirect_flag = true;
        _redirect_url = url;
    }
    //判断是否是短链接
    bool Close() {
        // 没有Connection字段，或者有Connection但是值是close，则都是短链接，否则就是长连接
        if (HasHeader("Connection") == true && GetHeader("Connection") == "keep-alive") {
            return false;
        }
        return true;
    }
};
typedef enum {
    RECV_HTTP_ERROR,
    RECV_HTTP_LINE,
    RECV_HTTP_HEAD,
    RECV_HTTP_BODY,
    RECV_HTTP_OVER
}HttpRecvStatu;

#define MAX_LINE 8192
class HttpContext {
private:
    int _resp_statu; //响应状态码
    HttpRecvStatu _recv_statu; //当前接收及解析的阶段状态
    HttpRequest _request;  //已经解析得到的请求信息
private:
    bool ParseHttpLine(const std::string &line) {
        std::smatch matches;
        std::regex e("(GET|HEAD|POST|PUT|DELETE) ([^?]*)(?:\\?(.*))? (HTTP/1\\.[01])(?:\n|\r\n)?", std::regex::icase);
        bool ret = std::regex_match(line, matches, e);
        if (ret == false) {
            _recv_statu = RECV_HTTP_ERROR;
            _resp_statu = 400;//BAD REQUEST
            return false;
        }
        //0 : GET /bitejiuyeke/login?user=xiaoming&pass=123123 HTTP/1.1
        //1 : GET
        //2 : /bitejiuyeke/login
        //3 : user=xiaoming&pass=123123
        //4 : HTTP/1.1
        //请求方法的获取
        _request._method = matches[1];
        std::transform(_request._method.begin(), _request._method.end(), _request._method.begin(), ::toupper);
        //资源路径的获取，需要进行URL解码操作，但是不需要+转空格
        _request._path = Util::UrlDecode(matches[2], false);
        //协议版本的获取
        _request._version = matches[4];
        //查询字符串的获取与处理
        std::vector<std::string> query_string_arry;
        std::string query_string = matches[3];
        //查询字符串的格式 key=val&key=val....., 先以 & 符号进行分割，得到各个字串
        Util::Split(query_string, "&", &query_string_arry);
        //针对各个字串，以 = 符号进行分割，得到key 和val， 得到之后也需要进行URL解码
        for (auto &str : query_string_arry) {
            size_t pos = str.find("=");
            if (pos == std::string::npos) {
                _recv_statu = RECV_HTTP_ERROR;
                _resp_statu = 400;//BAD REQUEST
                return false;
            }
            std::string key = Util::UrlDecode(str.substr(0, pos), true);  
            std::string val = Util::UrlDecode(str.substr(pos + 1), true);
            _request.SetParam(key, val);
        }
        return true;
    }
    bool RecvHttpLine(Buffer *buf) {
        if (_recv_statu != RECV_HTTP_LINE) return false;
        //1. 获取一行数据，带有末尾的换行 
        std::string line = buf->GetLineAndPop();
        std::cout<<line<<std::endl;
        
        //2. 需要考虑的一些要素：缓冲区中的数据不足一行， 获取的一行数据超大
        if (line.size() == 0) {
            //缓冲区中的数据不足一行，则需要判断缓冲区的可读数据长度，如果很长了都不足一行，这是有问题的
            if (buf->ReadAbleSize() > MAX_LINE) {
                _recv_statu = RECV_HTTP_ERROR;
                _resp_statu = 414;//URI TOO LONG
                return false;
            }
            //缓冲区中数据不足一行，但是也不多，就等等新数据的到来
            return true;
        }
        if (line.size() > MAX_LINE) {
            _recv_statu = RECV_HTTP_ERROR;
            _resp_statu = 414;//URI TOO LONG
            return false;
        }
        bool ret = ParseHttpLine(line);
        if (ret == false) {
            return false;
        }
        //首行处理完毕，进入头部获取阶段
        _recv_statu = RECV_HTTP_HEAD;
        return true;
    }
    bool RecvHttpHead(Buffer *buf) {
        // 确保当前处于"正在接收HTTP头部"的状态
        if (_recv_statu != RECV_HTTP_HEAD) return false;
        //一行一行取出数据，直到遇到空行为止， 头部的格式 key: val\r\nkey: val\r\n....
        while(1){
            std::string line = buf->GetLineAndPop();// 从缓冲区获取一行并移除
            //2. 需要考虑的一些要素：缓冲区中的数据不足一行， 获取的一行数据超大
            if (line.size() == 0) {
                //没读到完整的句子（没有遇到\r\n）
                //缓冲区中积压的未处理数据已经超过了单行最大允许长度
                if (buf->ReadAbleSize() > MAX_LINE) {
                    _recv_statu = RECV_HTTP_ERROR;
                    _resp_statu = 414;//返回414错误，防止资源耗尽
                    return false;
                }
                //缓冲区中数据不足一行，继续等待数据
                return true;
            }
            //这一行本身是否过长
            if (line.size() > MAX_LINE) {
                _recv_statu = RECV_HTTP_ERROR;
                _resp_statu = 414;//URI TOO LONG
                return false;
            }
            if (line == "\n" || line == "\r\n") {
                break;
            }
            bool ret = ParseHttpHead(line);
            if (ret == false) {
                return false;
            }
        }
        //头部处理完毕，进入正文获取阶段
        _recv_statu = RECV_HTTP_BODY;
        return true;
    }
    bool ParseHttpHead(std::string &line) {
        //key: val\r\nkey: val\r\n....
        if (line.back() == '\n') line.pop_back();//末尾是换行则去掉换行字符
        if (line.back() == '\r') line.pop_back();//末尾是回车则去掉回车字符

        //分割报文
        size_t pos = line.find(": ");
        if (pos == std::string::npos) {
            _recv_statu = RECV_HTTP_ERROR;
            _resp_statu = 400;//
            return false;
        }
        std::string key = line.substr(0, pos);  
        std::string val = line.substr(pos + 2);
        _request.SetHeader(key, val);
        return true;
    }
    bool RecvHttpBody(Buffer *buf) {
        if (_recv_statu != RECV_HTTP_BODY) return false;
        //1. 获取正文长度
        size_t content_length = _request.ContentLength();
        if (content_length == 0) {
            //没有正文，则请求接收解析完毕
            _recv_statu = RECV_HTTP_OVER;
            return true;
        }
        //2. 当前已经接收了多少正文,其实就是往  _request._body 中放了多少数据了
        size_t real_len = content_length - _request._body.size();//实际还需要接收的正文长度
        //3. 接收正文放到body中，但是也要考虑当前缓冲区中的数据，是否是全部的正文
        //  3.1 缓冲区中数据，包含了当前请求的所有正文，则取出所需的数据
        if (buf->ReadAbleSize() >= real_len) {
            _request._body.append(buf->ReadPosition(), real_len);
            buf->MoveReadOffset(real_len);
            _recv_statu = RECV_HTTP_OVER;
            return true;
        }
        //  3.2 缓冲区中数据，无法满足当前正文的需要，数据不足，取出数据，然后等待新数据到来
        _request._body.append(buf->ReadPosition(), buf->ReadAbleSize());
        buf->MoveReadOffset(buf->ReadAbleSize());
        return true;
    }
public:
    HttpContext():_resp_statu(200), _recv_statu(RECV_HTTP_LINE) {}
    void ReSet() {
        _resp_statu = 200;
        _recv_statu = RECV_HTTP_LINE;
        _request.ReSet();
    }
    int RespStatu() { return _resp_statu; }
    HttpRecvStatu RecvStatu() { return _recv_statu; }
    HttpRequest &Request() { return _request; }
    //接收并解析HTTP请求
    void RecvHttpRequest(Buffer *buf) {
        //不同的状态，做不同的事情，但是这里不要break， 因为处理完请求行后，应该立即处理头部，而不是退出等新数据
        DBG_LOG("请求行处理结果: 新状态=%d, 错误码=%d", _recv_statu, _resp_statu);
        switch(_recv_statu) {
            case RECV_HTTP_LINE: RecvHttpLine(buf);
            DBG_LOG("请求行处理结果: 新状态=%d, 错误码=%d", _recv_statu, _resp_statu);
            case RECV_HTTP_HEAD: RecvHttpHead(buf);
            DBG_LOG("请求行处理结果: 新状态=%d, 错误码=%d", _recv_statu, _resp_statu);

            case RECV_HTTP_BODY: RecvHttpBody(buf);
            DBG_LOG("请求行处理结果: 新状态=%d, 错误码=%d", _recv_statu, _resp_statu);

        }
        return;
    }
};
//让用户快速搭建http服务器
class HttpServer{
private:
    using Handler = std::function<void(const HttpRequest&, HttpResponse *)>;
    //一堆映射表请求处理
    using Handlers = std::vector<std::pair<std::regex,Handler>>;
    Handlers _get_route;
    Handlers _post_route;
    Handlers _put_route;
    Handlers _delete_route;
    std::string _basedir;//静态资源根目录
    TcpServer _server;
private:
    //1. 组织一个错误展示页面
    void ErrorHandler(const HttpRequest &req, HttpResponse *rsp){
        //1. 组织一个错误展示页面
        std::string body;
        body += "<html>";
        body += "<head>";
        body += "<meta http-equiv='Content-Type' content='text/html;charset=utf-8'>";
        body += "</head>";
        body += "<body>";
        body += "<h1>";
        body += std::to_string(rsp->_statu);
        body += " ";
        body += Util::StatuDesc(rsp->_statu);
        body += "</h1>";
        body += "</body>";
        body += "</html>";
        //2. 将页面数据，当作响应正文，放入rsp中
        rsp->SetContent(body, "text/html");
    }
    //将HttpResponse中的要素按照http协议格式进行组织，发送
    void WriteReponse(const PtrConnection &conn, const HttpRequest &req, HttpResponse &rsp){
        //1. 先完善头部字段
        if (req.Close() == true) {
            rsp.SetHeader("Connection", "close");
        }else {
            rsp.SetHeader("Connection", "keep-alive");
        }
        if (rsp._body.empty() == false && rsp.HasHeader("Content-Length") == false) {
            rsp.SetHeader("Content-Length", std::to_string(rsp._body.size()));
        }
        if (rsp._body.empty() == false && rsp.HasHeader("Content-Type") == false) {
            rsp.SetHeader("Content-Type", "application/octet-stream");
        }
        if (rsp._redirect_flag == true) {
            rsp.SetHeader("Location", rsp._redirect_url);
        }
        //2. 将rsp中的要素，按照http协议格式进行组织
        std::stringstream rsp_str;
        rsp_str << req._version << " " << std::to_string(rsp._statu) << " " << Util::StatuDesc(rsp._statu) << "\r\n";
        for (auto &head : rsp._headers) {
            rsp_str << head.first << ": " << head.second << "\r\n";
        }
        rsp_str << "\r\n";
        rsp_str << rsp._body;
        //3. 发送数据
        conn->Send(rsp_str.str().c_str(), rsp_str.str().size());
    }
    bool IsFileHandler(const HttpRequest &req){
        // 1. 必须设置了静态资源根目录
        if (_basedir.empty()) {
            return false;
        }
        // 2. 请求方法，必须是GET / HEAD请求方法
        if (req._method != "GET" && req._method != "HEAD") {
            return false;
        }
        // 3. 请求的资源路径必须是一个合法路径
        if (Util::ValidPath(req._path) == false) {
            return false;
        }
        // 4. 请求的资源必须存在,且是一个普通文件
        //    有一种请求比较特殊 -- 目录：/, /image/， 这种情况给后边默认追加一个 index.html（访问首页）
        // index.html    /image/a.png
        // 不要忘了前缀的相对根目录,也就是将请求路径转换为实际存在的路径  /image/a.png  ->   ./wwwroot/image/a.png
        std::string req_path = _basedir + req._path;//为了避免直接修改请求的资源路径，因此定义一个临时对象
        if(req._path.back() =='/'){
            req_path += "index.html";//首页
        }
        //必须是个普通文件
        if(Util::IsRegular(req_path) == false){
            return false;
        }
        return true;
    }
    //静态资源的请求处理 --- 将静态资源文件的数据读取出来，放到rsp的_body中, 并设置mime
    void FileHandler(const HttpRequest &req, HttpResponse *rsp){
        //使请求路径完整
        std::string req_path = _basedir + req._path;
        if (req._path.back() == '/')  {
            req_path += "index.html";
        }
        bool ret = Util::ReadFile(req_path, &rsp->_body);
        if (ret == false) {
            return;
        }
        std::string mime = Util::ExtMime(req_path);
        rsp->SetHeader("Content-Type", mime);
        return;
    }
    //功能性请求的分类处理
    void Dispatcher(HttpRequest &req, HttpResponse *rsp, Handlers &handlers){
        //在对应请求方法的路由表中，查找是否含有对应资源请求的处理函数，有则调用，没有则发挥404
        //思想：路由表存储的时键值对 -- 正则表达式 & 处理函数
        //使用正则表达式，对请求的资源路径进行正则匹配，匹配成功就使用对应函数进行处理
        //  /numbers/(\d+)       /numbers/12345

        for (auto &handler : handlers) {
            const std::regex &re = handler.first;
            const Handler &functor = handler.second;
            bool ret = std::regex_match(req._path, req._matches, re);
            if (ret == false) {
                continue;
            }
            return functor(req, rsp);//传入请求信息，和空的rsp，执行处理函数
        }
        rsp->_statu = 404;
    }
    //路由匹配
    void Route(HttpRequest &req, HttpResponse *rsp){
        //1. 对请求进行分辨，是一个静态资源请求，还是一个功能性请求
        //   静态资源请求，则进行静态资源的处理
        //   功能性请求，则需要通过几个请求路由表来确定是否有处理函数
        //   既不是静态资源请求，也没有设置对应的功能性请求处理函数，就返回405
        if (IsFileHandler(req) == true) {
            //是一个静态资源请求, 则进行静态资源请求的处理
            return FileHandler(req, rsp);
        }
        if (req._method == "GET" || req._method == "HEAD") {
            return Dispatcher(req, rsp, _get_route);
        }else if (req._method == "POST") {
            return Dispatcher(req, rsp, _post_route);
        }else if (req._method == "PUT") {
            return Dispatcher(req, rsp, _put_route);
        }else if (req._method == "DELETE") {
            return Dispatcher(req, rsp, _delete_route);
        }
        rsp->_statu = 405;// Method Not Allowed
        return ;
    }
    //设置上下文
    void OnConnected(const PtrConnection &conn){
        conn->SetContext(HttpContext());
        DBG_LOG("NEW CONNECTION %p", conn.get());
    }
    //缓冲区数据解析+处理
    void OnMessage(const PtrConnection &conn, Buffer *buffer){
        //只要有数据就死循环读取
        while(buffer->ReadAbleSize()>0){
            
            //1.获取上下文
            HttpContext* context = conn->GetContext()->get<HttpContext>();
            //2. 通过上下文对缓冲区数据进行解析，得到HttpRequest对象
            //  1. 如果缓冲区的数据解析出错，就直接回复出错响应
            //  2. 如果解析正常，且请求已经获取完毕，才开始去进行处理
            context->RecvHttpRequest(buffer);
            HttpRequest &req = context->Request();
            HttpResponse rsp(context->RespStatu());
            if (context->RespStatu() >= 400) {
                //进行错误响应，关闭连接
                ErrorHandler(req, &rsp);//填充一个错误显示页面数据到rsp中
                WriteReponse(conn, req, rsp);//组织响应发送给客户端
                context->ReSet();
                //出错了就把缓冲区数据清空防止下次读出错
                buffer->MoveReadOffset(buffer->ReadAbleSize());
                conn->Shutdown();//关闭连接
                return;
            }
            //当前请求还没有接收完整,则退出，等新数据到来再重新继续处理
            if (context->RecvStatu() != RECV_HTTP_OVER) return;
            //走到这里肯定有数据
            //3. 请求路由 + 业务处理(里面判断静态还是动态)
            Route(req, &rsp);
            //4. 对HttpResponse进行组织发送
            WriteReponse(conn, req, rsp);
            //5. 重置上下文
            context->ReSet();
            //6. 根据长短连接判断是否关闭连接或者继续处理
            if (rsp.Close() == true) conn->Shutdown();//短链接则直接关闭
        }
        return;
    }

public:
    HttpServer(int port,int timeout=DEFALT_TIMEOUT):_server(port){
        _server.EnableInactiveRelease(timeout);
        _server.SetConnectedCallback(std::bind(&HttpServer::OnConnected, this, std::placeholders::_1));
        _server.SetMessageCallback(std::bind(&HttpServer::OnMessage, this, std::placeholders::_1, std::placeholders::_2));
    }
    //设置静态根目录
    void SetBaseDir(const std::string &path){
        assert(Util::IsDirectory(path) == true);
        _basedir = path;
    }
    //添加对应路由信息
    void Get(const std::string &pattern, const Handler &handler) {
        _get_route.push_back(std::make_pair(std::regex(pattern), handler));
    }
    void Post(const std::string &pattern, const Handler &handler) {
        _post_route.push_back(std::make_pair(std::regex(pattern), handler));
    }
    void Put(const std::string &pattern, const Handler &handler) {
        _put_route.push_back(std::make_pair(std::regex(pattern), handler));
    }
    void Delete(const std::string &pattern, const Handler &handler) {
        _delete_route.push_back(std::make_pair(std::regex(pattern), handler));
    }
    //设置线程池中线程数量
    void SetThreadCount(int count) {
        _server.SetThreadCount(count);
    }
    //启动服务器（开始监听）
    void Listen() {
        _server.Start();
    }
};